Self-closing valve assembly for a dispensing opening of a container

Abstract

A self-closing valve assembly for installation in a dispensing opening of a container, a seal cap or the like, includes a first closure element having a domed wall portion of resilient material incorporating a passage-opening, said wall portion being resiliently deformable from a closed position into an open position under the influence of a first differential pressure force resulting from pressures acting on its opposite surfaces, and a second closure element having a domed wall portion for sealing the passage-opening when the first closure element is in its closed position. In order to balance the pressure prvailing in a container provided with the valve assembly when a pressure-increasing squeezing force is no longer exerted on the container, the second closure element is adapted to be brought out of its sealing relationship with the passage-opening in the first closure element under the influence of a second differential pressure force resulting from pressures acting on its opposite surfaces, said second differential pressure force being directed oppositely to said first differential pressure force.

What is claimed is:  
     
       1. A self-closing valve assembly for installation in a dispensing opening of a container or in a seal cap, including a first closure element having a wall portion of resilient material incorporating a passage-opening, said wall portion being resiliently deformable from a closed position into an open position under the influence of a first differential pressure force resulting from pressures acting on the opposite surfaces of said wall portion, and a second closure element for sealing the passage-opening when the first closure element is in its closed position, wherein said second closure element can be brought out of its sealing relationship with the passage-opening in the first closure element under the influence of a second pressure force resulting from pressures acting on its opposite surfaces, said second differential pressure force being directed oppositely to said first differential pressure force, and wherein the wall portions of the first and second closure elements have domed configurations directed towards each other in a balanced state of the loads acting thereon. 
     
     
       2. A valve assembly according to claim  1 , wherein said second closure element comprises a wall portion of resilient material having at least one passage-opening displaced in a non-overlapping manner relative to the passage-opening in the first closure element. 
     
     
       3. A valve assembly according to claim  1 , wherein both closure elements are of an elastomeric material. 
     
     
       4. A valve assembly according to claim  1  wherein in the closed position of the first closure element when the second closure element seals the passage-opening of the first closure element, a surface portion of the second closure element sealingly engages from below the passage-opening against the first closure element.